The team set off beneath the waves to explore this spectacular archipelago. It is an exciting opportunity for the team to delve into a world that still largely remains a mystery to science. Venturing down in the Nadir, a specially equipped deep sea submersible, Liz goes in search of an elusive ocean giant, the mola, or sunfish, to understand more about its little-known behaviour in the deep. On the way back to the Alucia, Liz checks in on a playful sea lion population to see how they have been affected by a recent extreme weather event, El Nino. Back on board the Alucia, the team sets sail north for the most remote and inhospitable islands in the Galapagos - Wolf and Darwin. Here, Liz joins the team tagging and tracking hammerhead sharks that school at this location in huge numbers as they try to unlock the secrets of this stunning behaviour. But nothing can prepare the Alucia crew for the power of the ocean in this isolated marine wonderland.